Duplex 2205 ASTM A789 UNS S31803 Duplex Stainless Steel Seamless Tube
Duplex S31803 is also known as UNS S32205. This type of tubing is characterized by its dual-phase microstructure, combining features of both austenitic and ferritic stainless steels. Despite its high-performance characteristics, Duplex S31803 tubing is relatively cost-effective compared to other high-alloy steels. Its durability and longevity contribute to lower maintenance costs and longer service life, providing a cost-efficient solution for many industrial applications.
Equivalent Grade of ASTM A789 UNS S31803 Duplex Stainless Steel Tubes
| Grade |
UNS
No |
Old British |
Euronorm |
Swedish SS |
Japanese JIS |
| BS |
En |
No |
Name |
| 2205 |
S31803 / S32205 |
318S13 |
- |
1.4462 |
X2CrNiMoN22-5-3 |
2377 |
SUS 329J3L |
Physical Properties of ASTM A789 UNS S31803 Duplex Stainless Steel Tubes
| Grade |
Density
(kg/m3) |
Elastic
Modulus (GPa) |
Mean Co-eff of Thermal
Expansion (μm/m/°C) |
Thermal
Conductivity (W/m.K) |
Specific
Heat
0-100°C ( J/kg.K) |
Electrical
Resistivity
(nΩ.m) |
| 0-100°C |
0-315°C |
0-538°C |
at 100°C |
at 500°C |
| UNS S32205 / 2205 |
782 |
190 |
13.7 |
14.2 |
- |
19 |
- |
418 |
850 |
Mechanical Composition of ASTM A789 UNS S31803 Duplex Stainless Steel Tubes
| Grade |
Tensile Strength
(MPa) min |
Yield Strength
0.2% Proof
(MPa) min |
Elongation
(% in 50mm) min |
Hardness |
| Rockwell C (HR C) |
Brinell (HB) |
| UNS S32205 / 2205 |
621 |
448 |
25 |
31 max |
293 max |
Chemical Composition of ASTM A789 UNS S31803 Duplex Stainless Steel Tubes
| Grade |
|
C |
Mn |
Si |
P |
S |
Cr |
Mo |
Ni |
N |
| 2205 (UNS S31803) |
Min Max |
- 0.030 |
- 2.00 |
- 1.00 |
- 0.030 |
- 0.020 |
21.0 - 23.0 |
2.5 - 3.5 |
4.5 - 6.5 |
0.08 - 0.20 |
| 2205 (UNS S32205) |
Min Max |
- 0.030 |
- 2.00 |
- 1.00 |
- 0.030 |
- 0.020 |
22.0 - 23.0 |
3.0 - 3.5 |
4.5 - 6.5 |
0.14 - 0.20 |
General Duplex stainless steel information
2205 is the most widely used duplex (ferritic/austenitic) stainless steel grade. It finds applications due to both excellent corrosion resistance and high strength. The standard duplex S31803 composition has over the years been refined by many steel suppliers, and the resulting restricted composition range was endorsed as UNS S32205 in 1996. Duplex S32205 gives better guaranteed corrosion resistance, but for much of the Duplex S31803 currently produced also complies with Duplex S32205. 2205 is not generally suitable for use at temperatures above 300ºC as it suffers from precipitation of brittle micro-constituents, nor below -50ºC because of its ductile-to-brittle-transition.
Here are some of the key advantages of using duplex S31803 tubes:
-
Corrosion Resistance: Duplex S31803 tubes exhibit excellent resistance to corrosion in various environments, including chloride-containing and acidic environments, making them suitable for harsh industrial applications.
-
High Strength: These tubes have higher strength compared to austenitic stainless steels, allowing for thinner wall thicknesses and lighter weight designs while maintaining structural integrity.
-
Good Toughness: Duplex S31803 tubes offer good toughness, making them suitable for applications where impact resistance is important.
-
Good Weldability: They have good weldability characteristics, which simplifies the fabrication process and reduces the risk of welding defects.
-
High Temperature Resistance: Duplex S31803 tubes can withstand high temperatures, making them suitable for applications in elevated temperature environments.
-
Cost-Effective: Despite their superior properties, duplex S31803 tubes are relatively cost-effective compared to other high-performance materials.
-
Low Thermal Expansion: These tubes have low thermal expansion coefficients, which helps reduce the risk of thermal distortion in applications involving temperature fluctuations.
-
Erosion Resistance: Duplex S31803 tubes offer good resistance to erosion and erosion-corrosion, making them suitable for applications where abrasive substances are present.
Applications
-
Oil and Gas Industry
-
Chemical Processing
-
Desalination Plants
-
Power Generation
-
Heat Exchangers
-
Pulp and Paper Industry
-
Automotive Industry
-
Construction
